Agnelli & Nelson, the collective name of Northern Irish pair Chris Agnelli and Robbie Nelson (who also produce under the names Afterburn, Cortez, Green Atlas, A&N Project, and Quincey & Sonance), writers and producers of dance music, are notable for helping to define the genre of Trance music since 1997. Since 1997, Chris Agnelli and Robbie Nelson have been writing and producing dance music, of which their hits El Nino and Everyday have become classics of their genre. They have to date produced five top 30 hits in the United Kingdom, and countless remixes, from Armin van Buuren to U2. The pair have collaborated with other major artists, including Matt Darey, Jon the Dentist, Scott Bond, Solar Stone, and Chicane. They have also appeared on BBC Radio 1 six times to provide guest mixes. They produce music for Xtravaganza, and labels such as Tsunami and ID&T. On 11 October 2006 Chris Agnelli threatened to sue popular trance podcaster DJ Addison over copyright infringement for playing one of their songs. DJ Addison prompty removed the song from the podcast, but continued to receive legal threats by Chris Agnelli. DJ Addison has since shut down the entire podcast over the ordeal.